// Copyright 2014 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

/*
 * Copyright (C) 2006, 2007, 2008, 2009 Apple Inc. All rights reserved.
 * Copyright (C) 2008 Nokia Corporation and/or its subsidiary(-ies)
 * Copyright (C) 2008, 2009 Torch Mobile Inc. All rights reserved.
 *     (http://www.torchmobile.com/)
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1.  Redistributions of source code must retain the above copyright
 *     notice, this list of conditions and the following disclaimer.
 * 2.  Redistributions in binary form must reproduce the above copyright
 *     notice, this list of conditions and the following disclaimer in the
 *     documentation and/or other materials provided with the distribution.
 * 3.  Neither the name of Apple Computer, Inc. ("Apple") nor the names of
 *     its contributors may be used to endorse or promote products derived
 *     from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "AS IS" AND ANY
 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED. IN NO EVENT SHALL APPLE OR ITS CONTRIBUTORS BE LIABLE FOR ANY
 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#include "content/renderer/history_entry.h"

#include "content/renderer/render_frame_impl.h"
#include "content/renderer/render_view_impl.h"
#include "third_party/WebKit/public/web/WebLocalFrame.h"

using blink::WebFrame;
using blink::WebHistoryItem;

namespace content {

HistoryEntry::HistoryNode* HistoryEntry::HistoryNode::AddChild(
    const WebHistoryItem& item)
{
    children_->push_back(new HistoryNode(entry_, item));
    return children_->back();
}

HistoryEntry::HistoryNode* HistoryEntry::HistoryNode::AddChild()
{
    return AddChild(WebHistoryItem());
}

HistoryEntry::HistoryNode* HistoryEntry::HistoryNode::CloneAndReplace(
    const base::WeakPtr<HistoryEntry>& new_entry,
    const WebHistoryItem& new_item,
    bool clone_children_of_target,
    RenderFrameImpl* target_frame,
    RenderFrameImpl* current_frame)
{
    bool is_target_frame = target_frame == current_frame;
    const WebHistoryItem& item_for_create = is_target_frame ? new_item : item_;
    HistoryNode* new_history_node = new HistoryNode(new_entry, item_for_create);

    // Use the last committed history item for the frame rather than item_, since
    // the latter may not accurately reflect which URL is currently committed in
    // the frame.  See https://crbug.com/612713#c12.
    const WebHistoryItem& current_item = current_frame->current_history_item();
    if (is_target_frame && clone_children_of_target && !current_item.isNull()) {
        // TODO(creis): Setting the document sequence number here appears to be
        // unnecessary.  Remove this block if this DCHECK never fires.
        DCHECK_EQ(current_item.documentSequenceNumber(),
            new_history_node->item().documentSequenceNumber());
    }

    // TODO(creis): This needs to be updated to handle HistoryEntry in
    // subframe processes, where the main frame isn't guaranteed to be in the
    // same process.
    if (current_frame && (clone_children_of_target || !is_target_frame)) {
        for (WebFrame* child = current_frame->GetWebFrame()->firstChild(); child;
             child = child->nextSibling()) {
            RenderFrameImpl* child_render_frame = RenderFrameImpl::FromWebFrame(child);
            // TODO(creis): A child frame may be a RenderFrameProxy.  We should still
            // process its children, but that will be possible when we move this code
            // to the browser process in https://crbug.com/236848.
            if (!child_render_frame)
                continue;
            HistoryNode* child_history_node = entry_->GetHistoryNodeForFrame(child_render_frame);
            if (!child_history_node)
                continue;
            HistoryNode* new_child_node = child_history_node->CloneAndReplace(new_entry,
                new_item,
                clone_children_of_target,
                target_frame,
                child_render_frame);
            new_history_node->children_->push_back(new_child_node);
        }
    }
    return new_history_node;
}

void HistoryEntry::HistoryNode::set_item(const WebHistoryItem& item)
{
    DCHECK(!item.isNull());
    entry_->unique_names_to_items_[item.target().utf8()] = this;
    unique_names_.push_back(item.target().utf8());
    item_ = item;
}

HistoryEntry::HistoryNode::HistoryNode(const base::WeakPtr<HistoryEntry>& entry,
    const WebHistoryItem& item)
    : entry_(entry)
{
    if (!item.isNull())
        set_item(item);
    children_.reset(new ScopedVector<HistoryNode>);
}

HistoryEntry::HistoryNode::~HistoryNode()
{
    if (!entry_ || item_.isNull())
        return;

    for (const std::string& name : unique_names_) {
        if (entry_->unique_names_to_items_[name] == this)
            entry_->unique_names_to_items_.erase(name);
    }
}

void HistoryEntry::HistoryNode::RemoveChildren()
{
    children_.reset(new ScopedVector<HistoryNode>);
}

HistoryEntry::HistoryEntry()
    : weak_ptr_factory_(this)
{
    root_.reset(
        new HistoryNode(weak_ptr_factory_.GetWeakPtr(), WebHistoryItem()));
}

HistoryEntry::~HistoryEntry()
{
}

HistoryEntry::HistoryEntry(const WebHistoryItem& root)
    : weak_ptr_factory_(this)
{
    root_.reset(new HistoryNode(weak_ptr_factory_.GetWeakPtr(), root));
}

HistoryEntry* HistoryEntry::CloneAndReplace(const WebHistoryItem& new_item,
    bool clone_children_of_target,
    RenderFrameImpl* target_frame,
    RenderViewImpl* render_view)
{
    HistoryEntry* new_entry = new HistoryEntry();
    new_entry->root_.reset(
        root_->CloneAndReplace(new_entry->weak_ptr_factory_.GetWeakPtr(),
            new_item, clone_children_of_target, target_frame,
            render_view->GetMainRenderFrame()));
    return new_entry;
}

HistoryEntry::HistoryNode* HistoryEntry::GetHistoryNodeForFrame(
    RenderFrameImpl* frame)
{
    if (!frame->GetWebFrame()->parent())
        return root_history_node();
    return unique_names_to_items_[frame->GetWebFrame()->uniqueName().utf8()];
}

WebHistoryItem HistoryEntry::GetItemForFrame(RenderFrameImpl* frame)
{
    if (HistoryNode* history_node = GetHistoryNodeForFrame(frame))
        return history_node->item();
    return WebHistoryItem();
}

} // namespace content
